April 28 (Reuters) - Canadian base metal miner First Quantum Minerals Ltd reported a bigger-than-expected quarterly profit as copper production costs fell and production rose in its Zambia operations.

Copper production increased about 30 percent to 119,287 tonnes while sales jumped 44 percent to 131,267 tonnes in the first quarter.

The company said in January that power supply at its mines - Kalumbila Minerals, Kansanshi, Sentinel - in Zambia improved following arrival of the rainy season.

Zambia power companies earlier this year cut electricity supply to mining firms by 30 percent.

First Quantum said on Thursday the material uncertainty regarding its ability to meet the net debt to EBITDA ratio covenant under the debt financing agreements has been removed.

The company, which is developing the massive Cobre Panama project, sold in March its Finnish mine Kevitsa to Swedish mining and smelting group Boliden for $712 million.

Net earnings from continuing operations attributable to First Quantum was $49 million in first quarter, compared with a loss of $78 million a year earlier.

Excluding items, it earned 9 cents per share, beating the average analyst estimate of 5 cents.

Total cost of copper production fell 22 percent to $1.86 per pound in the first three months of 2016.

Sales revenue rose 20 percent to $720 million.

Up to Thursday’s close of C$9.16, shares of the company had fallen nearly 50 percent in the past 12 months, compared with a 30 percent fall in the S&P/TSE Canadian Mining Index. (Reporting by Manish Parashar in Bengaluru; Editing by Sriraj Kalluvila)